MF and SS are the most common forms of CTCL. The etiology of this disease is still unknown. Patients may go for months to years with skin abnormalities before being diagnosed. MF/SS is an indolent disease and patients with T1 disease have a normal life expectancy. Patients who undergo transformation to large-cell lymphoma (8% to 23% of patients) have a poor prognosis, with mean survival ranging from 2 to 19 months. Treatment for MF/SS continues to be palliative. There are many new therapies that are currently being investigated in clinical trials, and the DAB(389)IL-2 fusion protein was recently approved for the treatment of refractory MF/SS.

PCBCL is defined as a B-cell lymphoma originating in the skin. There is no evidence of extracutaneous disease at presentation and for 6 months after diagnosis, as assessed by adequate staging procedures. Currently, the European Organization for Research and Treatment of Cancer classification is the most concise disease classification scheme, dividing the subtypes of PCBCL by clinical behavior and histopathologic findings. Based on this classification, the most common subtype of PCBCL is follicular center cell lymphoma. PCBCL is generally an indolent form of lymphoma with a good prognosis. Although local cutaneous recurrences are observed in 25% to 68% of patients, dissemination to internal organs is rare. Five-year survival rates typically range from 89% to 96%. A specific subtype, large B-cell lymphoma of the leg, is noted to have a poorer prognosis, with a 5-year survival rate of 58%. Overly aggressive treatment of PCBCL has not been shown to improve survival or prevent relapse. The treatment of choice usually varies depending on the type of PCBCL, the body surface area, and the location of the involvement, as well as the age and general health condition of the patient. The majority of studies indicate that PCBCL is highly responsive to radiation therapy. Polychemotherapy should be reserved for involvement of noncontiguous anatomic sites or those with extracutaneous spread.

Summary:Allogeneic hematopoietic stem cell transplantation should be considered as a therapeutic option for patients with generalized erythoderma or tumor stage MF. Indeed, the only curative option for MF may be an allogeneic transplant. Bone Marrow Transplantation (2000) 25, 111-113. Keywords: allogeneic hematopoietic stem cell transplant; mycosis fungoides; cutaneous T cell lymphoma Mycosis fungoides (MF) is a low-grade lymphoma that primarily manifests as cutaneous plaques or tumors. 1,2 Progression is accompanied by spread to lymph nodes and visceral organs. Histopathology reveals an epidermotropic lymphocytic infiltrate composed of atypical lymphocytes. 3 The atypical cells may also be seen in the peripheral blood and are characterized by their cerebriform or hyperconvoluted nuclear detail. MF cells are of the T cell lineage and usually have a CD4 ϩ CD45RO ϩ memory-helper phenotype. 4 The natural history of MF is usually indolent. Over many years MF may evolve from premalignant cutaneous lesions and scaly erythematous patches into palpable plaques and finally tumors. The mean survival for patients with early patch lesions may exceed 10-15 years. However, patients with generalized erythroderma or tumor at the time of presentation have a poorer prognosis with a median survival of 2-4 years. Early stage lesions are treated with psoralen and ultraviolet light A (PUVA), topical chemotherapy, extracorporeal photophoresis, interferon, and/or electron beam irradiation. 5,6 Advanced disease is treated with interferon, retinoids or combination chemotherapy regimens, with mixed results. 5,7 To our knowledge, we report the first case of reinduction of clinical and histologic remission following withdrawal of immunosuppressive medication after allogeneic hematopoietic stem cell transplantation, providing evidence for an immunologic graft-versus-MF effect. Case reportA 27-year-old black woman was diagnosed with mycosis fungoides (stage T3 N1 M0). She had failed multiple prior therapies including PUVA, PUVA and interferon, six cycles of CHOP (cyclophosphamide, adriamycin, vincristine, prednisone), and two cycles of 9-aminocamptothecin. The patient's skin was diffusely infiltrated with patches, plaques and tumors. Lymphatic and visceral organs were involved. An allogeneic HLA matched sibling transplant was performed using an unmanipulated marrow and CD34 immunoselected blood graft. Conditioning was with cyclophosphamide (200 mg/kg) and total body irradiation (1200 cGy). The post-transplant course was complicated by acute graft-versus-host disease (grade II) that resolved on corticosteroid and cyclosporine immunosuppressive therapy.The patient remained in complete remission for 9 months when new plaques were noted over the right thigh and chest (Figure 1a). Relapse of MF was confirmed by skin biopsy (Figure 1b and c). Since there was no clinical evidence of GVHD, prophylactic immunosuppression with cyclosporine was discontinued. Within 1 month, the plaques resolved and were replaced by flat and scaly hypopigmented patches....